Recently, accompanied by rapid growth of information-related appliances and communication appliances such as personal computers, video cameras and portable phones, development of batteries used as the power source thereof has been regarded important. Moreover, also in the automobile industry, and the like, development of high output and high capacity batteries has been promoted for electric automobiles or hybrid automobiles. Nowadays, among the various batteries, lithium batteries attract attention in regard to the high energy density.
Since the lithium batteries currently commercially available utilize an electrolyte including a combustible organic solvent, improvement is required in terms of the structure and material for prevention of a short circuit or for mounting a safety device for restraining temperature rise at the time of the short circuit. On the other hand, since all-solid-state batteries with the batteries processed to be in an all-solid state with the electrolyte replaced by a solid electrolyte layer do not utilize a combustible organic solvent in the battery, the safety device can be simplified so that it is considered that they can provide the excellent production cost and productivity.
As the solid electrolyte material used for such a solid electrolyte layer, sulfide solid electrolyte materials are known. Moreover, as the solvent for applying the sulfide solid electrolyte materials in a wet process, for example, the non-patent article 1 discloses use of a non-polar solvent such as toluene and heptane.